Pull-out frame with a protective plate for a break-contact arrangement

Abstract

A pull-out frame has drivers which are movably guided in a straight line at side walls, with a working surface which interacts with a working surface of a lifting lever which likewise is supported tiltably at the side walls. Interacting hook-like end parts of the driver and the lifting lever block, in the rest condition, tilting of the lifting lever. If required, end faces of the end parts of the driver and of the lifting lever meet each other in order to exert an additional restoring force on the lifting lever.

What is claimed is: 
     
       1. A pull-out frame for a switchgear arranged movably, having a stationary break-contact arrangement comprising: a protective plate for securing the contact arrangement against electrical shorting vertically movable in guide means between a first rest position and a second operating position;   means for actuating the protective plate comprising means for transforming part of a travel distance of the switchgear into a lifting motion of the protective plate;   driver means responsive to a restoring force and a lifting lever stationarily supported cooperating with the driver means;   said driver means and lifting lever having working surfaces facing each other;   said driver means being guided at a side wall of the pull-out frame and movable in a straight line in a direction of the travel path of the switchgear;   the working surfaces comprising the sole means for transmitting the force between the driver means and the lifting lever; and   the driver means and the lifting lever having hooklike end parts cooperating in a form-locking manner in the rest position of the device for blocking the lifting lever and the overlap of the end parts corresponding to a displacement of the driver to be traveled, starting from the rest position until contact is made by the working surfaces.   
     
     
       2. The pull-out frame recited in claim 1, wherein the driver means has a support surface adjacent the working surface thereof, the support surface supporting the weight of the protective plate as transmitted through the lifting lever when the pull-out frame is in the second operating position. 
     
     
       3. The pull-out frame recited in claim 1 wherein the support surface comprises an outside surface of the hook-like end part facing the lifting lever. 
     
     
       4. The pull-out frame recited in claim 1 wherein the lifting lever has a pivot bearing which is arranged in a plane lying above the support surface of the driver means, and the hooklike end parts of the driver means and the lifting lever have end faces opposite each other. 
     
     
       5. The pull-out frame recited in claim 1, wherein the driver means in its rest position extends up to a front edge of the pull-out frame on an operating side, and has near an end thereof an opening for a securing member blocking the driver means against actuation.